Measurement of Anti-Saccharomyces cerevisiae Antibodies in Human Feces as an Indicator of Crohn's Disease James Boone1, M.S., William Sandborn2, M.D., Lisa Pélanne1, M.S., David Lyerly1, Ph.D. 1TECHLAB®, Inc., Blacksburg, VA and 2Mayo Clinic, Rochester, MN TM Introduction: Patient Population: ASCA-CHEK Test Results for The method of determining the presence Ulcerative colitis (UC): 37 patients Patient Population and Controls Total Fecal ASCA Fecal ASCA Assessments Total Positive Negative of serum ASCA as a marker of Crohn's comprised of 15 females and 22 males N = 120 N=86 Crohn's Ulcerative disease colitis Total IBD 86 37.2% (32) 62.8% (54) disease has been used for the ranging in age from 21-70. (Crohn's disease and Fecal ASCA 27 5 differentiation between Crohn's disease ulcerative positive Crohn's disease (CD): 49 patients colitis) and ulcerative colitis and has been Fecal ASCA 22 32 comprised of 23 females and 26 males negative Total Crohn's 49 55.1% (27) 44.9% (22) previously published. In the following disease ranging in age from 21-78. Healthy / IBS study, we describe the first noninvasive N=120 Crohn's Ulcerative Irritable bowel syndrome (IBS): 22 patients Total Ulcerative 37 13.5% (5) 86.5% (32) disease colitis colitis method for determining the presence of Fecal ASCA 27 6 comprised of 20 females and 2 males Total Active 22 4.6% (1) 96.4% (21) positive fecal ASCA. Our approach provides a IBS ranging in age 19-78. Total Healthy 12 0 100.0% (12) Fecal ASCA 22 65 Controls negative highly specific method utilizing the extract Healthy control (HC): 12 persons of Saccharomyces cerevisiae for measuring comprised of 8 females and 4 males Statistical Analysis of Test Results total fecal ASCA as an aid to distinguish 1Crohn's 2Crohn’s 1 N=86 disease vs disease vs ranging in age from 20-79. 2 N=120 Ulcerative UC, IBS Crohn's disease from other gastro- colitis and HC Results: intestinal illnesses such as ulcerative Sensitivity 55.1% 55.1% Immunoglobulin Typing of ASCA in Human Specificity 86.5% 91.6% colitis and irritable bowel syndrome (IBS). - Fecal Specimens Predictive 84.4% 81.8% Pos Value Anti- Anti- Anti- Anti- Anti- Anti- Aim: Predictive 59.3% 74.7% Patient human human human human human human Neg Value Number Disease IgA IgAsec IgD IgM IgG Ig To describe a novel method for detecting Conjugate Conjugate Conjugate Conjugate Conjugate Conjugate Correlation 68.6% 76.7% 1 Crohn’s + + - + + + ASCA in human feces and evaluate the disease Group Mean SD OD P Value clinical utility for distinguishing Crohn's 2 Crohn’s + + - + - + ID OD Range disease CDvsUC,IBS,HC CD 1.183 0.794 0.341-3.000 p < 0.005 disease from ulcerative colitis and IBS. 3 Crohn’s - - - - - - disease CDvsUC UC 0.382 0.113 0.382-0.113 p < 0.05 Methods: 4 Crohn’s + + ND + - + disease CDvsIBS IBS 0.091 0.038 0.052-0.238 p < 0.005 Fecal ASCA levels were determined 5 Crohn’s + + ND - - + disease CDvsHC qualitatively by an enzyme-linked HC 0.091 0.019 0.054-0.124 p < 0.005 6 Crohn’s + + ND + - + immunoassay (ASCA-CHEK™ ;TechLab®, disease Conclusion: 7 Ulcerative - - - - - - Inc.). The immunoassay uses anti-human colitis ! Results show that fecal ASCA is specific immunoglobulin antibody conjugated to 8 Ulcerative - - - - - + colitis and useful for indicating CD. HRP and microwells coated with Serum Yeast - - - + + + Saccharomyces cerevisiae antigens. Fecal Control allergy ! Sensitivity and specificity is similar or specimens were diluted 1:20 in the kit better than that reported for serum based ND= Not done diluent and results were determined by ASCA tests. measurement of the optical density (OD) Note: The single UC patient that ! Based on Ig assays, IgA, IgAsec and IgM at 450nm/620nm. Results of > 0.200 were reacted with the human Ig-specific are the primary ASCA detected in feces. considered positive for the presence of conjugate tested negative for IgE fecal ASCA. Typing of immunoglobulins immunoglobulin. ! Fecal ASCA may be useful to couple with in feces was done using specific human Ig fecal lactoferrin (IBD-CHEK™ ) for assessing patients suspected of having IBD. conjugates. James Boone, M.S., TECHLAB ®, Inc., Blacksburg, VA e-mail: [email protected] .